Design issues and implementation of internet-based process control systems

Abstract

The Internet provides great potential for the high-level control of process plants. Internet-based process control is a new concept which has been received much attention in previous years. However, little work has so far been done aimed at developing systematic design methods for the design of such Internet-based process control systems. In this paper, five essential design issues that arise from web-related features of Internet-based process control have been investigated: requirement specification, architecture selection, web-based interface design, supervision control, and system safety checking. A water tank control system is used to demonstrate our design methodology. Uniquely, video feedback, text-based chatting, and a whiteboard are embedded in the system and shared by multiple communicating users. Virtual supervision parameter control is implemented to overcome the dynamic time delays caused by the Internet traffic. The experimental results show that the Internet-based control system for the water tank can have a similar behaviour to the local control system if properly designed.